This nonprovisional application claims the benefit of U.S. Provisional Application No. 60/460,875, filed Apr. 8, 2003 and Provisional Application No. 60/405,321, filed Aug. 23, 2002.
The invention relates to cannulas and clamping methods. More specifically, the invention relates to cannulas, cannula mount assemblies and clamping methods for perfusing one or more organs to monitor, treat, sustain and/or restore the viability of the organ(s) and/or for transporting and/or storing the organ(s).
Various devices have been developed that couple the anatomy of an organ being perfused to a machine or other equipment. Such devices are typically referred to as perfusion clamps or simply cannulas. Although the term cannula in general use has other meanings, the term cannula is used generically throughout the specification to refer to a clamp or other device that provides a connection through which a fluid flow may be established.
Currently, perfusionists select between two types of cannulas, depending on whether an aortic patch is available. A first type of cannula, as described in U.S. Pat. No. 5,728,115 to Westcott et al., which is hereby incorporated by reference, is shown in FIGS. 1-3. A clamping device (cannula) 10 is used to couple the perfusion cannula to the renal aorta 34. The clamp 10 includes two longitudinal members 12 and 14 which pivot about a pin 16. The proximal end of the member 12 includes an integral handle 18, while the proximal end of the member 14 includes an integral handle 20. The distal end of the member 12 includes an integral clamp head 24, while the distal end of the member 14 includes an integral clamp head 26. Clamp head 26 includes a nipple 28 attached thereto. Movement of the handles 18 and 20 toward one another forces the members 12 and 14 to pivot about the pin 16, thereby forcing the clamp heads 24 and 26 of the members 12 and 14 away from one another. A spring 22 is positioned between the handles 18 and 20 in order to bias the handles apart. This, in turn, tends to force the clamp heads 24 and 26 together. Therefore, the clamp heads 24 and 26 of the distal ends of the members 12 and 14 are engaged in clamping relationship unless an external compressive force is applied to the handles 18 and 20.
The distal end of the member 12 comprises an elongated, hollow, annular clamp head 24. A lumen 32 extends through the nipple 28.
In use, the clamp 10 is attached to the renal aorta 34 of a donor organ such as a kidney 36 by opening the clamp 10, passing the distal end 38 of the renal aorta 34 through the annular clamp head 24, holding the distal end 38 of the renal aorta 34 over the annular clamp head 24, and releasing pressure on the handles of the clamp 10 in order to allow the clamp head 26 to engage the distal end 38 of the renal aorta 34 against the annular clamp head 24. A catheter 40 may then be attached to the nipple 28 in order to provide perfusion of liquid through the lumen 32 and into the renal aorta 34.
A second type of cannula 50, used when no aortic patch is available, is shown in FIG. 4. No aortic patch may be available due to anatomical constraints or a living donor recovery. An infuse line (not shown) is connected to a top tube portion 52 of the cannula 50. A lower tube portion 54 of the cannula is inserted into the renal artery. The lower tube portion 54 may be sutured into place.